Silver chloride

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Endpoint:

particle size distribution (granulometry)

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is marketed or used in a non solid or granular form

Description of key information

This registration dossier covers the production and use of silver chloride in two different contexts: 
(i) production of AgCl as an on-site isolated intermediate during the production of silver metal. During the technical processes involved, silver chloride is not obtained as a dry product, but only in the form of slurries or wet filter-cakes. In some cases where the filter-cake is dried, residual moisture always remains in the intermediate product, causing the material to adhere and to agglomerate. Thus, silver chloride as an intermediate never occurs in a form in which the particle size can be determined experimentally. 
(ii) production of AgCl in a photographic silver halide emulsion. These silver chloride crystals are precipitated by the reaction of silver nitrate with one or more soluble (sodium, potassium, ammonium) chloride in an aqueous gelatin solution. Thus the silver chloride crystals are formed in a liquid gelatin medium, and at all stages between formation and the further use they are contained in either a liquid gelatin medium or a gel. There is no spontaneous generation of dry particulates so that the experimental determination of particle size is not relevant. For further details and references, please refer to the document prepared by the Imaging and Printing Association, which is attached to the corresponding endpoint study record in the technical dossier.
In consequence, testing for particle size is not technically feasible and was thus omitted in accordance with Annex XI, section 2 of Regulation (EC) No. 1907/2006 (REACH).